Hesperochiron is a small genus of flowering plants in the waterleaf family Hydrophyllaceae (order Boraginales), containing just two accepted species native to western North America. The genus was described by Sereno Watson (S.Watson) and has sometimes been treated within the broader Boraginaceae.
Plants are compact, thick-rooted perennial herbs that grow in squat patches at ground level. The oblong green leaves reach 7–8 cm long and 2–3 cm wide and are often covered with fine hairs. Flowers are bluish-white with distinctive yellow throats and appear briefly in early spring. The genus favors wet microhabitats such as seepy meadows and moist areas within the sagebrush steppe of the American West.
The two species are generally similar in appearance. Hesperochiron pumilus (dwarf hesperochiron) bears flowers that superficially resemble those of wild strawberry but can be distinguished by its five stamens and elliptical leaves. Hesperochiron nanus (California hesperochiron) produces slightly larger flowers. H. californicus is treated as a synonym of H. nanus by Plants of the World Online, though World Flora Online accepts it as a separate species.
Distribution
Hesperochiron is native to western North America, occurring in moist microhabitats including seepy meadows and wet areas within the sagebrush steppe. Hesperochiron pumilus blooms briefly in early spring in sagebrush steppe environments.
Taxonomy Notes
The genus was described by Sereno Watson and is placed in family Hydrophyllaceae within the order Boraginales. Some checklists, including certain GBIF datasets, treat Hydrophyllaceae as part of the broader Boraginaceae. As of December 2025, Plants of the World Online accepts two species (H. nanus and H. pumilus), treating H. californicus and H. campanulatus as synonyms; World Flora Online accepts all four as distinct species.
